"Jon Arne Jørgensen" <jonarne@xxxxxxxxxx> wrote: >On Mon, May 20, 2013 at 06:33:20AM -0400, Andy Walls wrote: >> "Jon Arne Jørgensen" <jonarne@xxxxxxxxxx> wrote: >> >> >Hi, >> >I've recently discovered that the smi2021 device have some pretty >> >specific >> >needs for the setup of the gm7113c chip. >> > >> >Both the smi2021 driver and the stk1160 driver needs registers >> >0x14 -> 0x17 to be zeroed, this is what forced me to add the gm7113c >> >chip to the saa7115 driver in the first place. >> > >> >Then Timo reported that the Terratec Grabby hwrev2 needs some of the >> >initial register settings to be changed for the device to work. >> >He posted a small list of required changes. >> >One of these changes is a change to register 0x12 which sets >> >up what to output on the RTS0 pin on the chip. >> > >> >Then I discovered that the smi2021 needs the V-Flag in the SAV/EAV >> >to be generated by VREF - whatever that means :). >> >That is, I need bit 7 to be clear and bit 6 to be set in register >0x10. >> >To have the device behave correctly. >> > >> >Both the change for the smi2021 driver and the changes for the >Terratec >> >device are pretty hardware specific. >> >They should probably not be part of the generic gm7113c setup. >> > >> >I would also guess that if other devices with the gm7113c chip >should >> >surface, these devices might also have different needs for the setup >of >> >the chip. >> > >> >I'm not sure what would be the correct way to handle these >> >differences. >> >The only sollution I'we tried is to bypass the saa7115 >> >driver, and push the needed changes directly over usb to the device, >> >after the initial setup is sent by the saa7115 driver. >> >This is a major hack, and the changes should probably go through >> >the saa7115 driver. >> > >> >Should the saa7115 driver be extended with an interface to change >> >random >> >register settings, or does the i2c subsystem already have a way to >> >handle this? >> > >> >Any idea about what might could be a better sollution? >> > >> >Best regards >> >Jon Arne Jørgensen >> > >> >-- >> >To unsubscribe from this list: send the line "unsubscribe >linux-media" >> >in >> >the body of a message to majordomo@xxxxxxxxxxxxxxx >> >More majordomo info at http://vger.kernel.org/majordomo-info.html >> >> For v4l2_subdev's there is a way to pass in platform/bridge device >specific data so initialization can be different than the default, >based on the needs of the bridge driver. > >Ok, can you give any pointers to any documentation/source files I can >look at for this? > >> >> As for the meaning of the V (Vertical) flag in Start Active Video >(SAV) / End Active Video (EAV) markers, the VESA VIP 1.x standard >explains that. Basically they are codes embedded in digitized video >rasters horizontal blanking interval that describe the current video >line and delimit their start and end. >> >> The V flag probably means a line in the vertical blanking interval >(VBI), but I can't recall. >> > >I'm sorry, I was a bit quick with that comment. >I know what the SAV/EAV and V-flag is. I just don't know what it means >that the V-flag is >generated by VREF. > >> Regards, >> Andy >> -- >> To unsubscribe from this list: send the line "unsubscribe >linux-media" in >> the body of a message to majordomo@xxxxxxxxxxxxxxx >> More majordomo info at http://vger.kernel.org/majordomo-info.html >-- >To unsubscribe from this list: send the line "unsubscribe linux-media" >in >the body of a message to majordomo@xxxxxxxxxxxxxxx >More majordomo info at http://vger.kernel.org/majordomo-info.html http://lxr.free-electrons.com/source/drivers/media/i2c/wm8775.c#L232 The bttv driver, IIRC, has the wm8775 driver initialize differently for the Nova S card. FWIW, the defaults for the wm8775 driver are generally those needed by the ivtv driver. Regards, Andy -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html